Dispensing apparatus

ABSTRACT

A projectile contains an explosive charge and a fuse assembly which carries axially spaced groups of angularly spaced bundles of chaff and axially spaced explosive charges. Each bundle has an explosive charge. In order to form a cloud of chaff, the explosive charge in the projectile is detonated so that the fuse assembly and the bundles of chaff are ejected. The fuse is ignited by the detonation. The groups are ejected progressively from the fuse assembly, by detonation of the charges in the fuse assembly, the bundles of each group being blasted laterally from the fuse assembly, by the respective explosive charge. Each bundle is disintegrated after a predetermined time interval by its own explosive charge. All the charges and the fuse are set to detonate at predetermined time intervals so that the resultant cloud has a specific shape.

United ttes atet [1 1 Lawrence 1 Aug. 19, 1975 1 1 DISPENSING APPARATUS [75] Inventor: John Charles Lawrence, London,

England 22 Filed: July 9, 1973 [21] Appl. No.: 377,214

3,730,098 5/1973 Edwards 102/63 Primary I5.\'att1it1erVerlin R. Pendegrass Attorney, Agent, or Firm-Christensen, OConnor, Garrison & Havelka 5 7 ABSTRACT A projectile contains an explosive charge and a fuse assembly which carries axially spaced groups of angularly spaced bundles of chaff and axially spaced explosive charges. Each bundle has an explosive charge. In order to form a cloud of chaff, the explosive charge in the projectile is detonated so that the fuse assembly and the bundles of chaff are ejected. The fuse is ignited by the detonation. The groups are ejected progressively from the fuse assembly, by detonation of the charges in the fuse assembly, the bundles of each group being blasted laterally from the fuse assembly, by the respective explosive charge. Each bundle is disintegrated after a predetermined time interval by its own explosive charge. All the charges and the fuse are set to detonate at predetermined time intervals so that the resultant cloud has a specific shape.

21 Claims, 2 Drawing Figures DISPENSING APPARATUS This invention relates to the formation of a cloud of radar reflecting chaff within the atmosphere.

According to one aspect of this invention there is provided apparatus for forming a cloud of radar reflecting chaff comprising bundles of radar reflecting chaff and ejector means for ejecting the bundles from a projectile in flight, each bundle being arranged to disintegrate at the end of a predetermined time interval after ejection from the projectile so that, once all the bundles have been disintegrated the chaff is scattered within the atmosphere to form a cloud of a substantially predetermined form.

The ejector means may be arranged to eject groups of bundles of chaff laterally with respect to the flight path of the projectile at spaced intervals along the flight path so as to form a substantially spherical cloud. The ejector means may be arranged'to eject each bundle of each group laterally along a respective path which extends radially from the flight path in a different direction to the paths of the other bundles of the group.

The ejector means may include an explosive charge, the arrangement being such that bundles of chaff are ejected from the projectile by explosion of the explosive charge. Conveniently the ejector means includes a number of explosive charges, the arrangement being such that each group of bundles is ejected by explosion of a respective explosive charge. Each bundle may include a further explosive charge and is arranged to be disintegrated by detonation of the further explosive charge. Furthermore each bundle may include a fuse which is arranged to be detonated by explosion of the respective explosive charge which is arranged to eject the bundle laterally with respect to the flight path, each fuse determining the time interval betwen lateral ejection and disintegration of the respective bundle.

The ejector means may comprise a tubular assembly, that part of each bundle which includes said fuse being spigotted into a radial aperture through the tubular wall of the tubular assembly, the respective explosive charge being housed within the portion of the bore of the tubular assembly with which the radial aperture communicates. Each bore portion which houses an explosive charge may be spaced from the juxtaposed bore portion or portions which also house an explosive charge by a bore portion of reduced diameter which delays ignition of the explosive charge which is further from the initially ignited explosive charge. Conveniently the tubular assembly comprises a number of tubular elements screwed together end to end. Each tubular element may comprise a bore portion which houses an explosive charge and a juxtaposed bore portion of reduced diameter. The tubular assembly may include an end tubular element which defines a said bore portion of reduced diameter which serves to delay ignition of the initially ignited explosive charge. Conveniently the spigot part of each bundle is tubular and said fuse is housed within the bore thereof.

According to another aspect of this invention there is provided a bundle of radar reflecting chaff for use in apparatus according to the preceding aspect, comprising chaff packed within a peripheral band and carrying a fuse which is adapted to be ignited by ejection of the bundle from a projectile in flight, the fuse being arranged so that the bundle disintegrates when the fuse has burnt through at the end of a predetermined period of time. The fuse may be arranged to burn through the peripheral band so that the bundle disintegrates, or to ignite an explosive charge in the bundle, the bundle being disintegrated by explosion of the explosive charge. The fuse may be housed within the bore of a tubular spigot which projects outwardly from the peripheral band.

In accordance with another aspect of this invention bundles of radar reflecting chaff are ejected from a projectile in flight and, at the end of a respective predetermined time interval, each bundle of chaff is disintegrated and the chaff scattered within the atmosphere so that, once all the bundles have been disintegrated and the chaff scattered, the scattered chaff forms a cloud of a substantially predetermined form.

Preferably groups of bundles of chaff are ejected laterally with respect to the flight path of the projectile at spaced intervals along the flight path to form a substantially spherical cloud. Conveniently each bundle of each group is ejected laterally along a respective path which extends radially from the flight path in a different direction to the paths of the other bundles of the group.

Bundles of chaff may be ejected from the projectile by the detonation of an explosive charge. Where groups of bundles are ejected laterally at spaced intervals along the flight path, each group may be ejected by the detonation of a respective explosive charge. Each bundle may be disintegrated by detonation of a further explosive charge. Conveniently the further explosive charge may be detonated by a fuse which was ignited by explosion of the respective explosive charge which ejected the bundle laterally with respect to the flight path, each fuse determining the predetermined time interval between lateral ejection and disintegration of the respective bundle.

One embodiment of this invention will be described how by way of example with reference to the accompanying drawings of which:

FIG. 1 is a perspective view of appartus according to the invention ejected from a projectile to form a cloud of radar reflecting chaff; and

FIG. 2 is a sectional view of part of the apparatus shown in FIG. 1.

Referring to FIG. 1 of the drawings, a projectile 10 has a tubular casing 11 which extends forwardly from an aft portion 12 in which is housed a power plant (not shown). A nose cone 13 is adapted to be fitted releasably to the front end of the tubular casing 11, so as to close an opening 14, defined by the front end of the tubular casing 11. The interior of the tubular casing 11 between the aft portion 12 and the nose cone 13 comprises a load carrying space. The detailed construction and operation of the projectile forms no part of the present invention.

A first explosive charge 15 is mounted at the end of the load carrying space nearer the aft portion 12. When the nose cone 13 is fitted to the front end of the tubular casing 11, it retains an elongate fuse assembly 16 within the load carrying space. The elongate fuse assembly 16, which will be described hereinafter in more detail with reference to FIG. 2, has one end 17 in contact with an annular thrust disc 18 which, in turn, is in contact with the first explosive charge 15 and extends from the first explosive charge 15 to the nose cone 13 along the axis of the tubular casing II. The elongate fuse assembly 16 carries a number of axially spaced groups of explosive charges within the load carrying space and supports a like number of axially spaced groups of bundles 19 of radar reflecting chaff (i.e. needles of aluminium foil) housed within the annular space defined between the elongate fuse assembly 16 and the inner wall of the tubular casing 11, the bundles 19 of each group being arranged in a circumferential array. Each bundle 19 comprises chaff 20 packed within a peripheral band 21 of a suitable material, such as stiff paper, and extends radially from the respective annular explosive charge to the inner wall of the tubular casing 11. The profile of each bundle 19, when viewed along the axis of the tubular casing 11, comprises inner and outer arcuate portions to one another at each circumferentially-spaced end by radial portions, both arcuate portions being concave to the centre of the tubular casing. The inner arcuate portion of each peripheral band 21 is formed of metal and carries a further fuse 22. The further fuse 22 is arranged to ignite a further explosive charge carried by the bundle 19. For reasons that will become more apparent from the description of the operation of the invention given below, the time taken for the further fuses 22 to burn through varies with the location of the respective bundle 19 along the axis of the tubular casing 11. Those bundles 19 at each end of the tubular casing 11 burn for the shortest time and those at the centre of the tubular casing 11 burn for the longest time.

Referring now to FIG. 2, the elongate fuse assembly 16 comprises a number of tubular elements screwed together end to end.

The end 17 is defined by an end tubular element 23 which has a counterbore 24 at the end 17 and an externally screw-threaded boss 25 at the other end. The main bore portion 26 and the larger diameter counterbore 24 are packed with explosive material. The boss 25 is screwed into a tapped hole in the juxtaposed end of another tubular element 27.

The tubular element 27, which is typical of all the tubular elements except the end tubular element 23, which has a stepped through bore, the larger diameter bore portion 29 extending over a major part of the axial length of the tubular elements 27 and being tapped at its outer end to define the said tapped hole. The larger diameter bore portion 29 is separated from the smaller diameter bore portion 30 bya frusto-conical bore portion 31. The smaller diameter bore portion 30 extends through an externally threaded boss 32 which is similar to the boss 25 and which is screwed into the tapped hole of the juxtaposed tubular element 27. The larger diameter bore portion 29 and the smaller diameter bore portion 30 are packed with explosive material, the frusto-conical bore portion being empty.

Each tubular element 27 has four circumferentially spaced radial apertures 33 which communicate with the bore portion 29. The aperture 33 of alternate tubular elements 27 are aligned axially and are displaced angularly with respect to the apertures 33 of the intervening tubular elements 27. Thus a diametrically opposed pair of apertures 33 are shown in alternate elements 27 in FIG. 2, none of the apertures 33 in the intervening elements 27 being visible in FIG. 2.

The metal inner arcuate portion of each peripheral band 21 comprises a tubular projection 34 which is spigotted into the respective aperture 33 and which has a stepped bore 35, the larger diameter portion of the stepped bore 35 being positioned radially outwardly with respect to the smaller diameter portion thereof. The stepped bore 35 is packed with explosive material which Constitutes the further fuse 22. FIG. 1 shows that each group of bundles 19 is surrounded by a paper band 36.

In operation of the invention, when it is desired to form a cloud of radar reflecting chaff, the projectile 10 is launched. When the projectile 10 reaches the area in the atmosphere in which the cloud is to be formed, the first explosive charge 15 is detonated. The resultant explosion separtes the nose cone 13 from the tubular casing 11, ignites the explosion material in the counterbore 24, and forces the bundles l9 and the fuse assembly forwardly out of the open front end of the tubular casing 11 (as shown in FIG. 1). The explosive material packed in the tubular elements 23 and 27 of the fuse assembly 16 is ignited progressively along the length of the fuse assembly 16. Ignition of each explosive charge contained in the larger diameter bore portion 29 is delayed until after ignition of the explosive charge contained in the juxtaposed larger diameter bore portion 29 by the influence of the intervening smaller diameter bore portion 30. Detonation of the explosive material packed in the larger diameter bore portion 29 of each tubular element 27 ignites the further fuse 22 of each bundle 19 of the surrounding group and blasts the bundles 19 of the surrounding group radially braking the surrounding band 36. At the end of a predetermined time interval, determined by the burning time of each further fuse 22, the further fuse 22 ignites the further explosive charge, the respective bundle l9 disintegrates and the chaff scatters within the atmosphere. It will be understood that the bundle 19 disintegrates at a radial distance from the fuse assembly 16 determined by the burning time of the respective further fuse 22. The burning times of the further fuses 22 are selected so that once all the bundles 19 have disintegrated and the chaff scattered, the resultant cloud of chaff is substantially spherical.

Use of explosive charges instead of other means (such as springs), for ejecting chaff bundles laterally enables chaff to be ejected further to one side of the flight path and thus facilitates formation of a substantially spherical cloud which is more desirable than elongated or cigar-shaped clouds. Delay of the disintegration of the bundles of chaff 19 until the moment most suitable for formation of the desired cloud shape results in the majority of the chafl being scattered at the periphery of the cloud, where it is needed, leads to the formation of substantially hollow clouds, and thus results in better utilisation of the payload of the projectile. The further fuses 22 may be arranged to burn through the peripheral band 21 instead of igniting the further explosive charge as described above.

What we claim is:

l. Appartus for forming, from a projectile in flight, a radar reflecting chaff cloud having a predetermined form, said appartus comprising:

a plurality of bundles of radar reflecting chaff;

ejection means, suitable for being carried by a projectile in flight, for ejecting said plurality of bundles of radar reflecting chaff from said projectile when said projectile is in flight; and,

bundle disintegration means forming a portion of each bundle for disintegrating each bundle subsequent to its being ejected from said projectile and scattering the chaff forming the bundle. each of said bundle disintegrating means including a timing mechanism for controlling the time interval between bundle ejection and bundle disintegration, said timing mechanisms controlling the bundle disintegration of their related bundles in a manner such that the time intervals between bundle ejection and bundle disintegration vary between selected ones of said bundles, said variations being controlled such that once all of the bundles have been disintegrated the scattered chaff forms a radar reflecting chaff cloud having a predetermined form, said form being determined by the controlled, variable time intervals occuring between bundle ejection and bundle disintegration.

2. Apparatus for forming a radar reflecting chafi' cloud as claimed in claim 1 wherein said plurality of bundles are arranged in groups and wherein said ejection means selectively ejects said groups laterally with respect to the flight path of said projectile at spaced intervals along the flight path whereby the combination of the spaced intervals between the ejection of said groups and the time intervals between ejection and bundle disintegration cooperate so as to form a substantially spherical cloud.

3. Appartus for forming a radar reflecting chaff cloud as claimed in claim 2, wherein the ejection path of each bundle of a particular group of bundles is radial with respect to the flight path of said projectile, the ejection path of each bundle of a particular group of bundles being different than the ejection path of the other bundles of said particular group of bundles.

4. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 1, wherein said ejection means includes an ejection explosive charge, the explosion of said ejection explosive charge ejecting said bundles of radar reflecting chaff from said projectile.

5. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 2, wherein said ejection means includes a plurality of ejection explosive charges, one ejection explosive charge being associated with each of said group of bundles in a manner such that the explosion of an ejection explosive charge associated with a particular group of bundles ejects that group of bundles from said projectile.

6. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 5, wherein said bundle disintegration means comprises a plurality of bundle explosive charges, one of said bundle explosive charges forming a portion of each bundle, the explosion of said bundles explosive charges causing the disintegration of the bundle associated therewith.

7. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 6, wherein each timing mechanism includes a variable time fuse extending to the bundle explosive charge of the associated bundle which is ignited by the explosion of an associated ejection explosive charge, each individual fuse determining the time interval between lateral ejection and disintegration of the bundle to which the fuse relates.

8. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 7, wherein said ejection means includes a tubular housing, said plurality of ejection explosive charges being longitudinally housed within said tubular housing at spaced intervals, said tubular housing including a plurality of radial apertures which selectively communicate with said plurality of ejection explosive charges. said fuses of said bundles being spigotted into said radial apertures so as to selectively contact said plurality of ejection explosive charges.

9. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 8, wherein said tubular housing is formed such that the ejection explosive charges are spaced from their adjacent ejection explosive charges along the longitudinal length of said tubular housing by a bore portion of reduced diameter, said smaller bore portion containing an explosive material that provides a delay between the ignition of an immediately subsequent ejection explosive charge subsequent to the explosion of immediately precedent ejection explosive charge, running from one end of said tubular housing to the other thereof.

10. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 8, wherein said tubular housing comprises a number of tubular elements screwed together end to end.

11. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 10, wherein each tubular element comprises a bore portion adapted to house one of said plurality of ejection explosive charges and a juxtaposed bore portion of reduced diameter.

12. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 11, wherein said tubular housing includes an end tubular element which defines a bore portion of reduced diameter, said end tubular element bore portion of reduced diameter acting to delay ignition of the ejection explosive charge nearest thereto.

13. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 12, wherein said bundle includes a tubular part which is spigotted into one of said apertures in said tubular housing, said fuses associated with said bundles being housed within the bores of said tubular parts.

14. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 13, wherein each of said plurality of bundles of radar reflecting chaff comprises radar reflecting chaff packed within a constrictive peripheral band, the bundle explosive charge associated with each of said bundles adapted to eliminate the constrictive effect of said peripheral band upon the explosion thereof and thereby release its associated chaff.

15. A method of forming a radar reflecting chaff cloud having a predetermined form comprising the steps of:

ejecting a plurality of bundles of radar reflecting chaff from a projectile in flight; and,

selectively disintegrating at predetermined time intervals the ejected bundles of radar reflecting chaff so as to scatter their radar reflecting chaff, the predetermined time intervals for certain of said bundles of radar reflecting chaff being different than the predetermined time intervals of others of said bundles of radar reflecting chaff, the differences in said time intervals being such that a time controlled selective scattering of the radar reflecting chaff occurs. said selective scattering causing the creation of a radar reflecting chaff cloud having a predetermined form, said predetermined form being related to the differences in said time intervals.

16. A method of forming a radar reflecting chaff cloud as claimed in claim 15, wherein groups of bundles of chaff are ejected laterally with respect to the flight path of said projectile at spaced intervals along said flight path such that a substantially spherical cloud is formed when all of said bundles have been disintegrated.

17. A method of forming a radar reflecting chaiT cloud as claimed in claim 16, wherein each bundle of each group is ejected laterally along a respective path which extends radially from the flight path of said projectile in a different direction to the path of the other bundles of the same group.

18. A method of forming a radar reflecting chaff cloud as claimed in claim 17, wherein the bundles of chaff are ejected from the projectile by the detonation of an ejection explosive charge.

19. A method of forming a radar reflecting chaff cloud as claimed in claim 17, wherein each group of bundles is ejected by the detonation of a respective ejection explosive charge.

20. A method of forming a radar reflecting chaff cloud as claimed in claim 19, wherein each bundle is disintegrated by the detonation of a bundle explosive charge.

21. A method of forming a radar reflecting chaff cloud as claimed in claim 20, wherein the bundle explosive charges are detonated by a fuse which is ignited by the explosion of the ejection explosive charge which ejected the bundle laterally with respect to the flight path of said projectile. the nature of each fuse determining the time interval between lateral ejection and disintegration of the respective bundle. 

1. Appartus for forming, from a projectile in flight, a radar reflecting chaff cloud having a predetermined form, said appartus comprising: a plurality of bundles of radar reflecting chaff; ejection means, suitable for being carried by a projectile in flight, for ejecting said plurality of bundles of radar reflecting chaff from said projectile when said projectile is in flight; and, bundle disintegration means forming a portion of each bundle for disintegrating each bundle subsequent to its being ejected from said projectile and scattering the chaff forming the bundle, each of said bundle disintegrating means including a timing mechanism for controlling the time interval between bundle ejection and bundle disintegration, said timing mechanisms controlling the bundle disintegration of their related bundles in a manner such that the time intervals between bundle ejection and bundle disintegration vary between selected ones of said bundles, said variations being controlled such that once all of the bundles have been disintegrated the scattered chaff forms a radar reflecting chaff cloud having a predetermined form, said form being determined by the controlled, variable time intervals occuring between bundle ejection and bundle disintegration.
 2. Apparatus for formIng a radar reflecting chaff cloud as claimed in claim 1 wherein said plurality of bundles are arranged in groups and wherein said ejection means selectively ejects said groups laterally with respect to the flight path of said projectile at spaced intervals along the flight path whereby the combination of the spaced intervals between the ejection of said groups and the time intervals between ejection and bundle disintegration cooperate so as to form a substantially spherical cloud.
 3. Appartus for forming a radar reflecting chaff cloud as claimed in claim 2, wherein the ejection path of each bundle of a particular group of bundles is radial with respect to the flight path of said projectile, the ejection path of each bundle of a particular group of bundles being different than the ejection path of the other bundles of said particular group of bundles.
 4. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 1, wherein said ejection means includes an ejection explosive charge, the explosion of said ejection explosive charge ejecting said bundles of radar reflecting chaff from said projectile.
 5. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 2, wherein said ejection means includes a plurality of ejection explosive charges, one ejection explosive charge being associated with each of said group of bundles in a manner such that the explosion of an ejection explosive charge associated with a particular group of bundles ejects that group of bundles from said projectile.
 6. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 5, wherein said bundle disintegration means comprises a plurality of bundle explosive charges, one of said bundle explosive charges forming a portion of each bundle, the explosion of said bundles explosive charges causing the disintegration of the bundle associated therewith.
 7. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 6, wherein each timing mechanism includes a variable time fuse extending to the bundle explosive charge of the associated bundle which is ignited by the explosion of an associated ejection explosive charge, each individual fuse determining the time interval between lateral ejection and disintegration of the bundle to which the fuse relates.
 8. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 7, wherein said ejection means includes a tubular housing, said plurality of ejection explosive charges being longitudinally housed within said tubular housing at spaced intervals, said tubular housing including a plurality of radial apertures which selectively communicate with said plurality of ejection explosive charges, said fuses of said bundles being spigotted into said radial apertures so as to selectively contact said plurality of ejection explosive charges.
 9. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 8, wherein said tubular housing is formed such that the ejection explosive charges are spaced from their adjacent ejection explosive charges along the longitudinal length of said tubular housing by a bore portion of reduced diameter, said smaller bore portion containing an explosive material that provides a delay between the ignition of an immediately subsequent ejection explosive charge subsequent to the explosion of immediately precedent ejection explosive charge, running from one end of said tubular housing to the other thereof.
 10. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 8, wherein said tubular housing comprises a number of tubular elements screwed together end to end.
 11. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 10, wherein each tubular element comprises a bore portion adapted to house one of said plurality of ejection explosive charges and a juxtaposed bore portion of reduced diameter.
 12. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 11, wherein said tubular housing includes an end tubular element which defines a bore portion of reduced diameter, said end tubular element bore portion of reduced diameter acting to delay ignition of the ejection explosive charge nearest thereto.
 13. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 12, wherein said bundle includes a tubular part which is spigotted into one of said apertures in said tubular housing, said fuses associated with said bundles being housed within the bores of said tubular parts.
 14. Apparatus for forming a radar reflecting chaff cloud as claimed in claim 13, wherein each of said plurality of bundles of radar reflecting chaff comprises radar reflecting chaff packed within a constrictive peripheral band, the bundle explosive charge associated with each of said bundles adapted to eliminate the constrictive effect of said peripheral band upon the explosion thereof and thereby release its associated chaff.
 15. A method of forming a radar reflecting chaff cloud having a predetermined form comprising the steps of: ejecting a plurality of bundles of radar reflecting chaff from a projectile in flight; and, selectively disintegrating at predetermined time intervals the ejected bundles of radar reflecting chaff so as to scatter their radar reflecting chaff, the predetermined time intervals for certain of said bundles of radar reflecting chaff being different than the predetermined time intervals of others of said bundles of radar reflecting chaff, the differences in said time intervals being such that a time controlled selective scattering of the radar reflecting chaff occurs, said selective scattering causing the creation of a radar reflecting chaff cloud having a predetermined form, said predetermined form being related to the differences in said time intervals.
 16. A method of forming a radar reflecting chaff cloud as claimed in claim 15, wherein groups of bundles of chaff are ejected laterally with respect to the flight path of said projectile at spaced intervals along said flight path such that a substantially spherical cloud is formed when all of said bundles have been disintegrated.
 17. A method of forming a radar reflecting chaff cloud as claimed in claim 16, wherein each bundle of each group is ejected laterally along a respective path which extends radially from the flight path of said projectile in a different direction to the path of the other bundles of the same group.
 18. A method of forming a radar reflecting chaff cloud as claimed in claim 17, wherein the bundles of chaff are ejected from the projectile by the detonation of an ejection explosive charge.
 19. A method of forming a radar reflecting chaff cloud as claimed in claim 17, wherein each group of bundles is ejected by the detonation of a respective ejection explosive charge.
 20. A method of forming a radar reflecting chaff cloud as claimed in claim 19, wherein each bundle is disintegrated by the detonation of a bundle explosive charge.
 21. A method of forming a radar reflecting chaff cloud as claimed in claim 20, wherein the bundle explosive charges are detonated by a fuse which is ignited by the explosion of the ejection explosive charge which ejected the bundle laterally with respect to the flight path of said projectile, the nature of each fuse determining the time interval between lateral ejection and disintegration of the respective bundle. 